Capstan-lathe.



A. FRISCH.

CAPSTAN LATHE.

APPLICATION FILED MAY 4. I916.

Patented June 5, 1917.

piainn erases rrnr AUGUST FRISCI-I, 0F ZfiRICI-I, SWITZERLAND, ASSIGNORTO THE FIRM OF A. FRISCI-I & (30., 0F Z'U'RIGH, SWITZERLAND.

GAPSTAN-LATHE.

Application filed May 4, 1916.

To all whom it may concern Be it known that I, QUJcUs'r Fniscrr, acitizen of the Republic of Switzerlaml, residing-at Ziirich,Switzerland, have invented new and useful Improvements in Capstan-Lathes; and 1 do hereby declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same, referencebeing had to the accom ianying drawing, and to letters or figures ofreference marked thereon, which form a part of this specification.

In capstan lathes as heretofore construct ed the mandrel carrying therevolving head is arranged either in line with the mandrel carrying thework or parallel to the latter mandrel in front thereof. This arrangement results in a capstan lathe of large di mensions and consequentlynecessitates the use of a considerable amount of material in itsconstruction and renders it expensive. Furthermore in capstan lathesknown a slide arrangement is provided for. the displacement of themandrel carrying the revolving head and such arrangement renders thelathe more complicated and consequently more costly than desirable.

The present invention has for its objectsto obviate these disadvantagesand to provide a capstan lathe the dimensions of which are as small aspossible and which is of extremely simple construction.

lrccording to the invention the mandrel carrying the revolving head ismounted in a headstock parallel to the work carrying mandrel andadjacent thereto and is rotatable and movable in a longitudinaldirection. The revolving head mandrel may be provided at or near itsrear end with an arm which carries a sectional nut adapted to engage ahollow lead screw mounted on the worlccarrying mandrel. Furthermore, forlimiting the rotary movement of the revolving head, a stop piece isprovided, fitted with a stop adjustable in the direction in which therevolving head rotates in order to insure an exact feed of the revolvinghead to any extent desired.

The accompanying illustrative drawing shows a constructional example ofcapstan lathe according to the invention.

Specification of Letters Patent.

alrea dy- Patented June 5, 1917.

Serial No. 95,370.

Figure 1 shows the lathe in front elevation,

Fig. 2 a side elevation thereof,

F 3 a plan.

Fig. 41 is a section corresponding to the line A-B of Fig. 3, some partsbeing omitted.

Fig. 5 shows a portion of the lathe in plan, the revolving head mandrelbeing in a ditfcrent position.

F (3 is a section corresptmding to the line CD of Fig. 3.

1 is a headstock having bearings 2 for the work-carrying mandrel 3which, at its front end is provided with a head 5 adapted to hold apiece of work 1. Mounted upon the rear end of the mandrel 3 is a hollowlead screw 6 which can be firmly held on the mandrel 3, for example bymanipulation of a hand wheel 7 which also serves to tighten up the head3 in order to hold the piece of work.

The mandrel 3 is also fitted with fast and loose pulleys associated witha driving belt 8 which can be displaced on the pulleys as desired bymeans of a belt fork 9.

In the headstock 1 there is mounted in bearings 10 parallel to thework-carrying mandrel 3 and adjacent thereto, a mandrel 11 on the frontend of which is a revolving head The revolving head 12 is provided withhandles and, according to the constructional example shown, canaccommodate six tools. The mandrel 11 is movable in the bearings 10 andis formed with two annular grooves 13. Arranged on the headstock 1 onboth sides of the mandrel 11 are two upwardly extending bars 14 that runparallel to each other and which are connected together at their upperends by a member 15 in contactfwith the headstock 1 and thus limit amovement of the revolving head to-, ward the headstock. The adjustmentscrews l9fextend' transverse to the direction of the mandrel 11 and fromtime to time one or the other of them can limit the rotation of therevolvinghead 12 in one direction by coming oppositeto and in contactwith a stop bar fixed on the headstock 1. A screw spindle 21 isadjustable in the stop bar 20 and forms a stop for therevolvingheadashereinafter described.

, j is for exam ale to be machined internall centricallyfi In this casethe adjustment screw;

19located1n the lOWtShPOSllllOIl serves as stop against rotation of therevolving head.

By moving the handle member 15 in a direc-, tion away irom the revolvinghead, when the:

latch device 17 is in engagement with one of the annular grooves 13,then the mandrel 11 will be so displaced that the tool lying'oppositethepiece of work will be moved intothe same until the lowest adjustmentscrew 18 If considerable strikes the headstock 1. longitudinal"displacement of the mandrel 11 be necessary then the latch device 17 canbe connected consecutively with both annular grooves 13.

riphery of the piece of work, then the screw spindle 21 will be soplaced that this spindle,

and not the bar .20, forms a stop for the revolving head 12. Byadjustment of the g screw spindle 21, the machining of the piece I ofwork can be controlled thereby. In such cases, when the tool is actingon the work from below the same, in which instance the efiected'by thespindle 21.

If it be desired to cut a screw thread on the work then anarm 23 isfirmly clamped on themandrel 11, which arm carries a sectional nut 24that engages withthe hollow lead screw 6. Owing to this the mandrel 11 Iwill be displaced correspondingly to the can be exchanged for similarparts with =Gopies of this patent maybe obtained for pitch of the threadof the screw 6and in accordance therewith so that a thread of corre--sponding pitch will be out upon the work. Thehollow screw 6 and thesectional nut 2d Mounted upon the screw spindle 21 are two stop nuts 22.

- Let it be assumed that the piece of work 4 carrying'mandrel mountedtherein, :a lead screw fitted over said work carrying mandrel, f

If the tool in operation is to act on the pef1,22s,e57

other pitch of screw thread in order to out another pitch of thread onthe work. I

' Instead ofthe stop formed by the screw spindle 21 a stop, movable bymeans of an eccentric or cam, could be provided. 2

The improved capstan lathe according to the presentinvention is of thesimplest construction and easiestmanipulation and all possibleoperations for a capstan lathe can be executed with it. The improvedcapstan lathe is moreover of very small. dimensions.

7 Having now particularly described and ascertainedlthe nature of saidinvention and in what manner the same is to be performed, I declare thatwhat I claim is:

1. In a capstan lathe, a headstock, a work- 2. In a capstan l' the,aheadstock, a workcarrying mandrel mounted therein, a rev0lving head,aimandrel carrying the latter mounted in the headstock parallel tothework-carrying mandrel and rotatable and movable in a longitudinaldirection, a stoppiece mounted on the revolving head adapted tolimittheturning movement of the latter and a stop for the revolving headadj ustable in the direction of rotationoif the latter.

3. "In a capstan lathe, a'headstock, a workcarrying mandrel mountedtherem, a lead screw fitted over said mandrel, a revolving head, amandrel carrying the latter and mounted in the headstock parallel to thework-carrying mandrel and rotatable and movable in longitudinaldirection, an arm fixed on the mandrel carrying the revolving head andprovided with a sectional nut engaging said lead screw, a stop-piecemounted .in' the revolving head adaptedto limit the turning movement ofthe latter, and a stop for said revolvinghead, adjustable in the. 2

direction of rotation of the latter.

In testimony that I claim the foregoing as I my invention I have signedmy name in presence of two subscriblng witnesses.

' I AUGUST FRISCH.

Witnesses:

CARL GUBLEB, ARNOLD LEHNER.

fiveie'ents eah by addressing the iflommissioner of Patents.WashingtomD; G. I p I

